Runway End Light for Airfield Ground Lighting

Runway end lights provide visual identification of the end of the runway and form part of the runway visual lighting system. They help distinguish the runway termination and support the interpretation of the overall runway lighting system, so they should be treated as a complete visual-aid system rather than simply a light fixture. They are selected according to the approved runway lighting layout, runway direction, threshold/end arrangement, optical requirements and electrical circuit configuration.

Runway end lights are red, fixed and unidirectional, showing red in the direction of the runway so that the end is recognised by an aircraft on the runway. An incorrect optical orientation can cause reduced visibility, incorrect visual information, non-compliant photometric performance, or excessive or insufficient intensity in the intended viewing sector.

Under ICAO Annex 14, runway end lights are provided on a runway equipped with runway edge lights, in a minimum number of lights (at least six) arranged across the runway end. They are placed on a line at right angles to the runway axis, as near the runway end as possible and not more than 3 m outside it. Confirm the arrangement and spacing against the edition in use.

It is a single fixture that shows green toward the approach and red toward the runway from one housing. FAA fixture types include L-862E (high-intensity elevated), L-861E (medium-intensity elevated) and L-850D (inset). The lens and colour orientation must be confirmed on the order, because a fixture installed the wrong way round gives the wrong colour in the wrong direction.

An elevated light is installed above the pavement on an approved mounting arrangement, with a frangible support, and its orientation and optical axis should match the approved layout. An inset light is installed substantially flush with the pavement where the airport design requires an in-pavement solution, so the housing, seating, pavement interface, drainage and sealing are critical parts of the installation. The approved airport layout determines the final configuration.

No. A fixture being electrically operational does not automatically demonstrate photometric compliance. Photometric performance should be evaluated against the applicable requirements for colour, intensity, beam distribution, horizontal and vertical coverage, optical direction and colour coordinates, and optical alignment is critical. Using LED technology also does not by itself establish compliance, because the complete fixture and optical system must satisfy the applicable technical requirements.

A typical arrangement is a CCR feeding a primary AGL cable, an isolating transformer, a secondary cable and the runway end light. Select the fixture together with the associated isolating transformer and series circuit, and review the rated operating current, series-circuit compatibility, power consumption, connector arrangement, intensity control compatibility and monitoring requirements. Incorrect selection can cause incorrect light output, improper intensity control, excessive loading, circuit instability, transformer stress, premature failure or monitoring abnormalities.

Verify the runway end location and centreline reference, fixture position and approved spacing, the optical direction, azimuth, elevation and correct colour direction, the correct isolating transformer, secondary cable, connector and circuit current, and the mounting, torque, seating, sealing and frangibility arrangement. Commissioning covers visual inspection, circuit continuity, insulation resistance, transformer verification, circuit current, CCR and intensity-step operation, monitoring where applicable and photometric verification where required.

A light that is off can come from an open series circuit, a failed light source, an isolating transformer fault, a connector failure, a secondary cable fault or an internal fixture fault. Low output can come from incorrect CCR intensity, optical contamination, LED degradation, damaged optics, incorrect alignment or electrical incompatibility. Intermittent operation can come from a loose connector, moisture ingress or a cable or transformer connection problem, and incorrect direction or visibility from incorrect orientation or optical configuration, or an incorrect replacement fixture. Work along the circuit from the CCR to the fixture before replacing components.

Confirm the airport and project, runway identification and direction, runway classification, approach category, threshold/end arrangement, elevated or inset configuration, required colour, optical direction, photometric requirements, light-source technology, series-circuit current, isolating transformer, connector type, mounting arrangement, environmental requirements, applicable standard and the manufacturer’s documentation, including compliance and type-test documents.

References include ICAO Annex 14 Vol. I (Chapter 5 on runway end lights, with the frangibility and siting provisions in Chapters 5 and 9), FAA AC 150/5340-30J on design and installation details for airport visual aids, and FAA AC 150/5345-46F on runway light fixtures, which lists the L-862E and L-861E elevated and L-850D inset threshold/end types. Also check DGCA India requirements, airport-specific specifications and the approved layout, and verify the applicable edition before procurement.

No. An open series circuit driven by a constant-current regulator can produce dangerously high voltage, and opening, cutting or disconnecting any part of an energised circuit can cause serious injury or death. Do not disconnect or reconnect a fixture’s secondary connector while the series circuit is energised, because an open secondary on a series isolating transformer can develop hazardous voltage and damage the transformer. De-energise the circuit at the regulator, apply the site lock-out / tag-out procedure, use the series circuit cut-out switch or an approved isolation device, and work on the movement area only under the airport’s permit-to-work system, with the runway or taxiway closed as required. See the electrical safety warning on this page.